A container mentioned in Patent Literature 1 is a representative example of a conventional bottle-shaped resin container.
The bottle-shaped resin container mentioned in Patent Literature 1 will be described with reference to FIGS. 24 and 25.
A bottle-shaped resin container 100 shown in FIG. 24 has a plastic bottle main body 102 and a plastic cap 104.
The bottle main body 102 includes a neck portion 106 and a body portion 108, which are integrally formed. The neck portion 106 has, on its outer periphery, a male threaded portion 110 as well as an annular jaw portion 112 and an annular flange portion 114 each forming a horizontally projecting portion, the male threaded portion, the jaw portion and the flange portion being formed downward from above in this order. The body portion 108 is a container portion which is filled with content such as drinking water.
The cap 104 includes a cap main body 116, a cap ring 118, and bridges 120 connecting the cap main body 116 and the cap ring 118 to each other.
The cap main body 116 has a female threaded portion 122 formed on its inner periphery, the female threaded portion 122 being screwed onto the male threaded portion 110. Screwing of the female threaded portion 122 onto the male threaded portion 110 allows the neck portion 106 to be closed by the cap 104.
The cap ring 118 is in a ring shape and its upper end is connected to the lower end of the cap main body 116 via the bridges 120 which are large in number. The cap ring 118 is formed so as to have a slightly larger internal diameter than the external diameter of the jaw portion 112 so that the cap ring 118 is fitted onto the jaw portion with a slight gap formed outside the jaw portion 112. Inside the cap ring 118, a plurality of stoppers 124 which are capable of engagement with the lower end of the jaw portion 112 from below are formed in a circumferential direction at a predetermined pitch so as to project in a direction toward the axis.
When the cap 104 is screwed onto the neck portion 106 of the bottle main body 102 after the bottle main body 102 is filled with content such as drinking water, the stoppers 124 are configured so that their upper ends are engaged with the lower surface of the jaw portion 112 after the stoppers 124 pass around the jaw portion 112. Then, in discharging the content from the bottle main body 102, the cap main body 116 is rotated in a direction in which the female threaded portion 122 is unscrewed from the male threaded portion 110, whereby the bridges 120 are broken by shear force. Thereafter, further rotation of the cap main body 116 in the same direction causes the cap 104 to be separated from the neck portion 106 and the state is as shown in FIG. 25. In such a state, the lower surface of the cap ring 118 approaches the upper surface of the flange portion 114 and the cap ring 118 is sandwiched between the jaw portion 112 and the flange portion 114 in a vertically immovable state.